The major function of absorbent articles such as disposable diapers and incontinence briefs or undergarments is to absorb and contain body exudates. Such articles are thus intended to prevent body exudates from soiling, wetting, or otherwise contaminating clothing or other articles, such as bedding, that come in contact with the wearer. The most common mode of failure for such products occurs when body exudates leak out of the gaps between the article and the wearer's leg or waist to adjacent clothing because they are not immediately absorbed within the article and the absorbent article is not able to sustain a good fit on the wearer such that gaps are created allowing the exudates to leak out of the absorbent article. For example, urine tends to be deposited onto the topsheet more rapidly than it can be absorbed and, therefore, the urine migrates to the gaps in the absorbent article where it can come in contact with clothing or other articles and can be absorbed by these articles. Additionally, loose fetal material that is not easily absorbed by the absorbent article tends to "float" on the liquid-receiving surface and work its way past the gaps in the article in the legs or waist of the wearer.
Contemporary disposable diapers have a topsheet, a backsheet, an absorbent core, and elasticized leg flaps generally formed from an elastic member being enclosed in the continuous topsheet and backsheet which extend beyond the edges of the absorbent core. These elasticized leg flaps prove effective generally to prevent wicking and overflow from the fluid laden diaper to clothing contacting the edges of the diaper in that the elasticized leg flaps present a fluid impervious barrier between the edge of the diaper and the contacting clothing, and in addition, provide a gasketing action about the legs of the wearer to maintain a seal about the leg and minimize gapping. However, leakage along the perimeter of the diaper may still occur. As the diaper is worn for longer periods of time, forces tend to act on the diaper to degrade the initial fit on the wearer. Large gaps and sagging of the diaper in the legs and waist are formed by the degradation in fit. Thus, as liquids are deposited onto the topsheet, some of the liquid is not immediately absorbed through the topsheet and migrates toward the edges of the diaper where it can leak through or past the gaps in the diaper and come in contact with clothing or undergarments where it can be absorbed by and wicked into such garments.
Disposable diapers may be provided with barrier cuffs which inhibit loose fecal material or gushes of urine or liquids from soiling the wearer's clothing. The barrier cuffs restrain the free flow of this material and provide a structure to hold such material within the diaper so that as such material freely floats or flows on the topsheet of the diaper, it is contained within the diaper. Despite the effectiveness of such structures in containing such material, it has been found that liquids can leak beyond the barrier cuffs and soil the wearer's clothing because the diaper construction does not promote a sustained fit of the diaper on the wearer. Additionally, the barrier cuffs may not be properly applied to the wearer such that good initial fit is not achieved and the sustained fit is often worse.
Examples of some disposable diapers and absorbent articles described in the patent literature are:
U.S. Pat. No. Re 26,151 which reissued Jan. 31, 1967 (originally U.S. Pat. No. 3,180,335, dated Apr. 27, 1965) to Robert C. Duncan discloses a disposable diaper having inwardly folded side flaps and means to fasten the ends of the inwardly folded edges of the side flaps in position over the face of the absorbent pad of the diaper.
U.S. Pat. No. 3,860,003 which issued to Kenneth Barclay Buell on Jan. 24, 1985 discloses contractible side portions for disposable diapers. Such diapers have outwardly extending side flaps and elastic members forming seals about the leg.
U.S. Pat. No. 4,490,148 which issued Dec. 25, 1984 to Bo Beckestrom discloses an incontinence brief or diaper that has inwardly folded side flaps that are fixed at their ends to the backsheet, and which side flaps have elasticized free edges. The Beckestrom patent follows the Duncan teaching that the side flaps are not secured in the crotch area. Beckestrom positions the points of fastening at the ends of the side flaps behind the waistband edges of the absorbent core, and fastens them to underlying portions of the backsheet.
U.S. Pat. No. 4,964,860 issued to Gipson et al. on Oct. 23, 1990 discloses a detachable two piece absorbent article having a disposable element having inflected side panels (FIG. 2). The disposable element is temporarily secured to a refastenable belt which holds the disposable assembly against the waist of the wearer.
U.S. Pat. No. 5,087,255 issued to Bret A. Sims on Feb. 11, 1992 discloses an absorbent article having an inflected barrier leg cuff which provides improved waist containment and fit. While this absorbent article has been effective, it is not economical to manufacture. The barrier leg cuff is manufactured independent of the absorbent core, backsheet and topsheet, and must be positioned and affixed to the topsheet as part of the manufacturing process.
Therefore, it is an object of the present invention to provide an absorbent article which has the improved containment characteristics of the inflected barrier cuff described in the Sims patent and the two piece garment of Gipson et al. but which is more convenient and efficient to manufacture and use.
It is an additional object of the present invention to provide an absorbent article having an inflected barrier cuff which acts as a restraint against the leakage of body exudates.
It is a still further object of the present invention to provide an absorbent article that is easy to apply to the wearer and promotes better containment by being less sensitive to variations in the application of the diaper and providing improved sustained fit.
These and other objects of the invention will be more readily apparent when considered in reference to the following description and when taken in connection with the accompanying drawings.